Electrical connector



Dec. 31, 1968 E. SCHMUED 3,419,844

ELECTRICAL CONNECTOR Filed July 12, 1965 'IIIIIIIIIIIAI "IIIII! III;

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INCL/NED PLANE J? 4 I v 110/ me United States Patent 3,419,844ELECTRICAL CONNECTOR Edgar Schmued, 5051 Palos Verdes Drive N., RollingHills Estates, Calif. 90274 Filed July 12, 1965, Ser. No. 471,334 2Claims. (Cl. 339-48) ABSTRACT OF THE DISCLOSURE A multi-pin connectorformed of a pair of mutually connectable terminal blocks in which leadwires are embedded, the terminal ends of the lead wires in one blockbeing electrically joined with the terminal ends of the lead wires inthe other block by ball shaped pellets of electrically conductive metalwire positioned and insulated from each other in an intermediate cavityprovided between the two terminal blocks.

My invention relates to electrical connectors and more particularly toan improved pressure electrical connector that is substantiallyinvulnerable to severe vibration and shock. My invention is directedprincipally to electrical connectors of the multi-pin type in which plugor pinconnector terminals are joined or coupled together by means offemale connectors, i.e., split sleeves of relatively ductile electricalconducting metal such as brass, copper or like material; the male pinsof one connector being inserted through one end of corresponding femaleconnector and the male pins of the other connector being insertedthrough the opposite ends thereof to form multiple electrical joints.

While these connectors work well enough in stationary equipment, vastnumbers of multi-pin connectors are currently being employed inmissiles, rockets and advanced aircraft, for example, whereinreliability of each and every system is of paramount importance. Asplit-second interruption in a single circuit can abort or cause a vitalmission to end in disaster. Frequently such failures can be traced to amultipin connector in which the female connector sleeve has spread apartor fractured due to extreme vibration and shock during launch andsubsequent operation, causing a short or break in a circuit that isvital to the operation or guidance of the vehicle. Moreover, suchvehicles are occasionally subjected to extremely high G-loads underwhich forces of destructive proportions are exerted upon the vehiclesystems and components.

It is therefore a primary object of my invention to provide a pressureconnector that is reliable and substantially invulnerable to severevibrations and shock over prolonged periods.

It is another object of my invention to provide a pressure connector foruse in aerospace vehicles and the like, which can be hermetically sealedagainst the intrusion of moisture and corrosive chemicals and may easilybe internally pressurized for use in unusual environmental conditions.

It is still another object of my invention to provide a pressureelectrical connector that is ideally suitable for use in aerospacevehicles, yet relatively simple in construction and economical tomanufacture.

Briefly, the pressure connector of my present invention, in onepreferred form, comprises a pair of mutally connectable terminal blocks,each electrically connected at one end thereof to a plurality ofconductors to be joined. Corresponding leads for the conductors areembedded in the terminal blocks, the leads terminating in an internallydisposed chamber that is defined between the terminal blocks whenmutually connected together.

Positioned in the chamber are a plurality of resilient connectors, onedisposed between each of the distal or terminal ends of the terminalblock leads, in electrical conduction contact therebetween, and meansfor retaining and insulating each of the resilient connector means fromone another.

My invention will be more easily understood, and other objects andadvantages more readily seen, by reference to the ensuing detaileddescription and appended drawings in which:

FIGURE 1 is a side elevational view in cross-section showing a preferredform of my invention,

FIGURE 2 is a fragmentary enlarged view showing the plate, aperture andresilient connector of my present invention,

FIGURE 3 is a plan view showing the plate, apertures, resilientconnectors, and indexing notch of my invention, and

FIGURE 4 is a side elevational view of a modified form of my invention.

A preferred form of my invention is shown in FIG- URE l in which twogroups 5 of electrical wires or conductors 6 bundled together in a cablesheath, or by harness straps (not shown), are joined together at theirdistal ends in terminal blocks 9 and 10 respectively. Each terminalblock is formed of a body 11 cast or molded of epoxy resin or othersuitable dielectric potting material having embedded therein a pluralityof lead wires 12. In all respects, terminal blocks 9 and 10 areidentical.

For convenience and ease of assembly the terminal blocks 9 and 10 areadapted to be assembled and fastened together in overlappingrelationship as shown, the faying or mutually connectable surfaces 13thereof being ac curately planed and ground to sufiicient flatness toform a void-free, flush interface at their joint.

Wire leads 12, joined with appropriate conductors 6 of each bundle 5,are arranged in predetermined relationship in their respective terminalblocks, being cut to appropriate lengths and bent at right angles sothat their distal ends are coterminus along a common plane ad acent tothe faying or interfacial surfaces 13 of the termlnal blocks.

A recess or cavity 15 is provided in the faying surfaces 13 of eachterminal block, being formed or machined therein in any convenientmanner, and aligned with each other to define a unitary internallydisposed chamber 16 between the terminal blocks when assembled andfastened together.

The cavities 15 extend a desired distance into each body 11, exposingalong the aforementioned common planes the terminal ends 14 of theprealigned lead wires 12 for interconnection. If desired, the ends 14 ofthe terminal block leads 12 in the chamber 16 maybe somewhat fiattenedand soldered to increase their contact area, or may be provided withstandard terminals (not shown) if desired.

In the chamber 16, intermediate the aligned lead wire terminals 12 ofeach terminal block 9 and 10, I provide a flat insulating wafer or plate17, fabricated of a durable dielectric material, the dimensions andshape around the edges being such as to produce a sliding fit within thechamber 16. Preferably, the thickness of plate 17 is slightly less thanthe depth of chamber 16 to provide a small clearance therein.

A plurality of apertures 19 are provided through plate 17 each of theapertures 19 being prearranged and located to correspond with thealigned terminal ends 14 of the terminal block leads 12 as shown.

In each aperture 19, I mount a ball or pellet 20, preferably formed ofspringy or resilient metal wool, i.e., filaments of a metal having goodelectrical conducting propm erties, such as copper, beryllium-copper, orlike material. The diameter of the conductor pellet 20 can be madeslightly greater than the depth of chamber 16, and hence the distancebetween the aligned terminal ends 14 of the terminal block leads 12.Thus, when the terminal blocks 9 and 10 are joined together andfastened, the resilient pellets are compressed between the terminalsurging the pellet material into tight electrical contact bcween eachpair of terminal ends 1 4.

It will also be seen that by flattening the pellets 20 between theterminals, the pellets will correspondingly expand in width and becomefirmly wedged within the con fines of their respective apertures 19.Thus it is readily apparent that an electrical union is formed betweenthe aligned terminal block leads, the nature of which is not subject toweakening, deforming or rupturing under prolonged or even indefiniteperiods of severe vibration, shock or G-loads.

To insure proper alignment of the apertures 19 in plate 17, an indexingnotch 22 is provided in one edge of plate H 17; a correspondingprotuberance or pin (not shown) being provided in the edge of one orboth cavities. Each aperture may be coded, i.e., marked withidentification means, as is well known in the art.

All that is necessary to hermetically seal the interior chamber 16against moisture and chemical intrusion is to provide aligned continuousseats or grooves 23 in the faying surfaces 13, or terminal blockinterfaces, between the terminal blocks 9 and 10, and intermediate thechamber 16 and the block exterior. An elastic O-ring 24 is provided,seated in the grooves 23 in the well known manner.

The terminal blocks 9 and 10 may be fastened together in any convenientmanner, one preferred manner being shown wherein a central bolt bore 27is drilled through the terminal block bodies 11 and a bolt 28 insertedtherethrough, a nut 29 being threaded 0n the bolt end extending throughthe opposite side substantially as shown. T 0 strengthen the assemblywashers 31 are provided at each end of bolt 28. To seal the bolt bore 27circumferential grooves 32 are provided in the terminal block body 11around the head 33 of bolt 28 and around the threaded end 34 thereof; anO-ring 35 being seated in each groove 32 as shown.

Where it is necessary to pressurize the internal chamber 16, space (notshown) may easily be provided within plate 17 for a small rupturablecapsule of C0 The foregoing example of the pressure connector of myinvention will satisfy most requirements. However, where space is aprimary problem, the dimensions around the combined terminal blocks maybe substantially reduced by designing the faying surfaces of theterminal block bodies in the form of inclined planes substantially asshown in FIGURE 4. In all other respects, the internal organization andarrangement of the terminal block leads, chamber, insulating plate,pellet connectors, O-ring grooves and seals remain substantially thesame as in the embodiment descirbed above with reference to FIG- URES1-3.

If desired, the bodies forming the terminal blocks may be confinedwithin shells or receptacles made of insulating material; these formsbeing well known to those skilled in the art.

Obviously the pressure connector of my invention is susceptible ofnumerous other forms and embodiments and I do not regard it as necessaryto exhaustively describe and show all or a part of the modifiedembodiments that will occur to those skilled in the art; such forms andmodifications being deemed to fall within the spirit and scope of myinvention, the gist of which is set forth in the following claims.

I claim:

1. In an electrical connector, the combination compris- (a) a pair ofsubstantially identical terminal blocks cast of dielectric material,each of said blocks having one side surface adapted to be joined withthe corresponding side surface of the other,

(b) a plurality of lead wires embedded in parallel relationship in eachof said blocks, each of said lead wires having one end thereof extendingfrom one end of its block which end is adjacent to said joining surfacethereof, each of said lead wires being bent at an angle in said block toposition the opposite end thereof at the surface of said side definingthe joining surface with said other block, said joining sides of saidblocks extending in a plane that is coextensive with the direction ofthe ends of said lead 'wires extending from said end of said block,

(c) means defining an airtight shallow chamber of uniform depth betweensaid joining surfaces of said terminal blocks, the ends of each of saidlead wires terminating in said chamber and aligned for interconnectiontherein,

((1) a compressible ball of electrically conductive wool positioned insaid chamber and compressed therein between said aligned ends of saidlead wires,

(e) a relatively thin fiat plate of insulating material in said chamber,said plate having apertures therethrough located and arranged inalignment with said ends of said lead wires to position and retain saidcompressible conductive balls between said aligned ends of said leadwires,

(f) a seal extending around said chamber between said joining surfacesof said terminal blocks,

(g) aligned bores extending transversely through each of said terminalblocks, and

(h) a fastening bolt extending through said aligned bore to fasten saidblocks together.

2. The electrical connector combination in claim 1 in which saidterminal block surfaces adapted to join in overlapping relationship areinclined planes.

References Cited UNITED STATES PATENTS 266,681 10/1882 Eaton 33992 XR1,743,888 1/ 1930 Hamister 33994 XR 2,400,647 5/1946 Kohring 3392212,486,195 10/1949 Munsey 33961 2,902,628 9/1959 Leno 33917 XR 3,158,41911/1964 Meyer et a1. 33918 3,235,832 2/1966 Buchanan et a1. 339220 XR3,126,520 4/1967 Herman 339-18 MARVIN A. CHAMPION, Primary Examiner.

PATRICK A. CLIFFORD, Assistant Examiner.

US. Cl. X.R. 3.39-92

